Answer:
Infinite Solutions
Step-by-step explanation:
x + y = 4
y = -x + 4
x + y = 4
x - x + 4 = 4
0 = 0
(4, -6) e (-2, 1)
a = Δy / Δx
a = (y-yo) / (x-xo)
a = [1-(-6)] / (-2-4)
Andy's age = x
Jeff's age = x-2
Andy's age in five years = x+5
Jeff's age in five years = x-2+5
The sum of their ages in five years = x+5 + x-2+5
x + 5 + x - 2 + 5 = 40
2x + 8 = 40
<u> -8 -8</u>
2x = 32
<u> :2 :2</u>
x = 16
x - 2 = 14
<u>Andy is 16 years old and Jeff is 14 years old</u>
Answer:
13
Step-by-step explanation:
where n is the number of terms, a1 is the first term and an is the last term. The sum of the first n terms of an arithmetic sequence is called an arithmetic series . Example 1: Find the sum of the first 20 terms of the arithmetic series if a1=5 and a20=62 .An arithmetic sequence is a sequence where the difference between any two consecutive terms is a constant. ... As with any recursive formula, the initial term of the sequence must be given. An explicit formula for an arithmetic sequence with common difference d is given by an=a1+d(n−1) a n = a 1 + d ( n − 1 ) .
